Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) narrates that the Prophet (peace and blessings be upon him) said: "The gates of the sky are opened for five things: the recitation of the Qur'an, the meeting of the two armies, the descent of rain, the supplication of the oppressed, and the adhan."
Imam al-Tabarani recorded this narration in al-Mu'jam al-Awsat and al-Mu'jam al-Saghir. Its chain contains a narrator, Hafs bin Sulayman al-Asadi, whom Imam Bukhari (may Allah have mercy on him), Imam Muslim, Yahya bin Ma'in, Imam Nasa'i (may Allah have mercy on him) and Ali bin al-Madini declared da'if (weak), while Imam Ahmad and Ibn Hibban declared him thiqah (trustworthy); however, he (Ibn Hibban) recorded the word al-Azdi in place of al-Asadi.
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الصلاة / 1850
Hadith Gradingمحدثین:إسنادہ ضعیف
Hadith Takhrij«المعجم الصغير للطبراني من اسمه سعيد 472 ، أخرجه المعجم الأوسط للطبراني برقم: 3646، وأخرجه المعجم الصغير للطبراني برقم: 444»